Re: [gentoo-user] tar over ssh

[John Jolet]

On Jan 24, 2006, at 9:10 PM, Ow Mun Heng wrote:

> On Tue, 2006-01-24 at 17:23 +0000, Francesco Riosa wrote:
>> Jeff wrote:
>>> Hey guys.
>>>
>>> I've got this big fat backup server with no space left on the
>>> hard drive
>>> to store a tar file. I'd like to pipe a tar through ssh, but not
>>> sure
>>> what the command would be. Something to the effect of:
>>>
>>> # cat /var/backup | ssh backup.homelan.com 'tar data.info.gz'
>>>
>>> So that, the data is actually being sent over ssh, and then
>>> archived on
>>> the destination machine.
>>>
>> tar -zcf - /var/backup | ssh backup.homelan.com "( cat >
>> data.info.gz  )"
>>
>
> There's another way. This assumes your originating server's CPU is
> slow/precious and you have a 16 way node on a backup server (HAHA!!)
>
> tar cf - /var/backup | ssh backup.homelan.com "gzip -c >
> filename.tar.gz"
>
> But you transfer the stream uncompressed, so more bits get
> transferred.
>
you're kidding, right?  Unless you've got a PII on the originating  
end and are using gigabit ethernet between the two nodes, compressing  
the data before transmission will almost always be faster.  I tested  
this scenerio extensively about 3 years ago, using linux, aix, and  
solaris hosts.  In no case was transferring uncompressed data faster  
than compressing (at least to some degree) the data on the  
originating server.  And frankly, no matter what you do...wouldn't  
you hope ALL the bits get transferred? :)
>
>
>
> --
> Ow Mun Heng
> Gentoo/Linux on DELL D600 1.4Ghz 1.5GB RAM
> 98% Microsoft(tm) Free!!
> Neuromancer 11:10:24 up 11:00, 6 users, load average: 1.08, 1.04, 1.15
>
>
> --
> gentoo-user@g.o mailing list
>

-- 
gentoo-user@g.o mailing list